Refrigerated fresh-cut fruit and vegetables are the most rapidly expanding area in produce sales. Shelf life for minimally processed produce depends on natural product senescence or spoilage organism decay. Shelf life limits, near-aseptic cutting facilities, refrigerated transportation, and refrigerated storage make it possible to ship precut cantaloupe coast to coast on a year-round basis. Thorough cantaloupe surface disinfection reduces potential spoilage organisms and harmful pathogens. We compared using vapor hydrogen peroxide and sulfur dioxide to the current practice of hypochlorite (HOCL) washing to reduce cantaloupe microbial load. After treatment, cantaloupe were stored in unsealed polyethylene bags at 2.2°C for 4 weeks. The HOCL treated fruit were scrubbed and soaked for 5 minutes in a commercial HOCL solution. After 4 weeks, the HOCL washed fruit had reduced visible molds compared to controls. Cantaloupes fumigated for 60 minutes with 5000 or 10,000 ppm sulfur dioxide developed sunken lesions but no significant decay after 4 weeks storage. Cantaloupes, treated 60 minutes with 3 mg·L–1 volume vapor hydrogen peroxide, did not show injury or significant decay after 4 weeks storage. Sulfur dioxide and vapor hydrogen peroxide show promise as alternatives to HOCL.
Transgenic Cantaloupe Charentais melons (Cucumis melo var. cantalupensis Naud. `Védrantais') exhibiting strong inhibition of ethylene production were used as a model to discriminate between ethylene-regulated and ethylene-independent ripening pathways. Compared to wild-type fruit, transgenic fruit did not undergo significant yellowing of the rind and softening of the flesh. However, these effects were completely reversed by treating transgenic fruit with 50 μL·L-1 exogenous ethylene. Pigmentation of the flesh occurred early before the onset of the climacteric and was thus unaffected by ethylene inhibition in transgenic fruit. Total soluble solids accumulated at the same rate in both types of fruit until 38 days after pollination when wild-type fruit abscissed. However, as ethylene-inhibited fruit failed to develop a peduncular abscission zone, they remained attached to the plant and accumulated higher amounts of sugars, mainly sucrose. Harvesting transgenic fruit resulted in a small but significant increase of internal ethylene associated with softening of the flesh.
The response of different doses of calcium sulfate or phosphogypsum (PG) on several postharvest quality parameters of `Laguna' cantaloupe hybrid were analyzed in the semi-arid San Francisco experiment station (UCLA), located in the Lara state, Venezuela. The experimental design was a completely randomized block with four treatments (0, 300, 600, and 1200 kg/ha, PG) with five replications. The PG was surface-spread on the irrigation furrows, 1 day before sowing. The fruits were harvested at maturity and stored under an average temperature of 28°C for posterior quality analysis. The PG treatments did not have any effect on the studied parameters: total soluble solids (°Brix), consistency (kg/cm2), diameter, and cavity of the fruit, pulp thickness, and dry and fresh matter. All of the parameters evaluated decreased during the 6 days of storage. These results could be because of the low doses of PG used or because the supply of calcium was not a limitation in these soils.
The objective of this study was to determine the effects of 1-MCP preharvest spray application on harvest synchrony, maturity, fruit quality, and marketable yield of cantaloupe. Seeds were planted in a commercial field on 16 Mar. (early planting, cv. Caravelle) and 4 Apr. (late planting, cv. Mission) 2005. Standard plant population, fertilization, irrigation, and pest control practices were followed. We evaluated three 1-MCP rates (5, 10, or 25 g·ha-1 a.i.) at three preharvest spraying times for the early (22, 15, and 7 days before harvest, DBH) or once for the late planting experiment (4 DBH). An additional test (late planting) compared fruit quality after storage for melons dipped with 1-MCP (0 or 10 mg·L-1). Fruits were harvested six times during June 2005 (early planting) and once on 19 July 2005 (late planting) and fruit quality parameters were measured at harvest and after storage. The preharvest 1-MCP application slightly delayed maturity and improved early harvest synchrony, but did not affect total marketable or yield by fruit size regardless of timing or rate of application. There was no effect of 1-MCP rate or application timing on fruit quality at harvest or after cold storage, except for an increased in fruit firmness (10%) in one of the six harvests. However, fruits treated with 1-MCP spray at 25 g·ha-1 a.i. (late planting) had higher firmness than those treated with lower rates after 9 days of storage. In addition, 1-MCP postharvest dipping significantly improved fruit firmness; however, a `greening' was evident in the fruit surface. Our results suggest that cantaloupe fruit quality was less affected by early preharvest spray application of 1-MCP applied at less than 25 g·ha-1 a.i. as compared to postharvest applications.
New fresh-cut melon products prepared from orange-fleshed honeydews have recently become available in retail markets. We compared fresh-cut chunks of orange-fleshed honeydew (`Temptation' and four breeding lines), green-fleshed honeydew (`Honey Brew'), and cantaloupe (`Cruiser'). All genotypes had similar respiration and ethylene production rates and soluble solids contents: genotype means for soluble solids contents were between 9.4% and 10.1 %. Five hundred untrained consumers preferred the flavor, texture, and overall eating quality of the orange honeydews to the green cultivar, with `Temptation' scoring highest. `Temptation' chunks were less firm at the time of processing and after 12 days storage than chunks prepared from all other genotypes. The color of orange-fleshed honeydew chunks was intermediate between that of cantaloupe and green-fleshed honeydew and the color was maintained during 12 days storage. Total aromatic volatiles from juice extracts of orange-fleshed honeydew chunks was 1.2 to 4.7 times higher than that of green-fleshed honeydew extracts and volatiles from cantaloupe was >4.8 fold greater than extracts from `Temptation' and >9.3 fold higher than that of other honeydew extracts. Many individual volatiles were identical in cantaloupe and honeydews; however, honeydew genotypes, particularly the orange-pigmented types, were distinctive from cantaloupe in having relatively high levels of various nonenyl and nonadienyl acetates of uncharacterized aromas. The results indicate that `Temptation' and other orange-fleshed honeydews are a promising new melon type for fresh-cut processing.
Abstract
Six cultivars of cantaloupe-type muskmelon (Cucumis melo L.), grown in central Pennsylvania, were harvested at the yellow full-slip, green full-slip, or half-slip stages of maturity and evaluated for quality after storage at 0° or 4.5°C. Fully ripe (yellow full-slip) melons had excellent appearance and flavor at harvest, but they deteriorated rapidly in storage, as shown by loss of flavor and ascorbic acid, development of stem-end cracks and decay, and water-soaking of the flesh. Of the 3 maturity stages, green full-slip melons had the highest soluble solids and ascorbic acid content and excellent flavor at harvest, and maintained flavor and appearance best in storage. Halfslip melons maintained a good appearance during storage, but were slightly inferior in flavor to full-slip melons. No evidence of chilling injury was found for melons harvested at any of the maturity stages and stored up to 2 weeks at 0° plus 1 day at 13°; in fact, melons stored at 0° were superior to those stored at 4.5° because less decay was evident.
A field study was conducted in south Texas in the spring 1990 to determine the effects of ground cover, planting method and drip irrigation rates on cantaloupe growth, yield and quality. Transplanting vs. direct seeding enhanced early vine growth with earlier yields, although direct seeding later caught up resulting in comparable final cumulative yields. Black polyethylene mulch also improved earliness but at the loser irrigation rate total yields were reduced due to deflection of rainfall by the mulch. Irrigation at .1, .3, .5, .7 and .9 times pan evaporation had little effect on final cumulative yields with exception to the .1 and .3 rates. Melon sugar content was highest for transplants with direct seeded melons becoming comparable only at mid to final harvest. The combined practices of transplanting and black polyethylene mulch resulted in a 14 day earliness advantage over the treatments that were direct seeded on bare soil although final yields were unaffected. No appreciable increase in soil salinity were found as a result of drip irrigation usage.
Chilling injury of cantaloupe melons (Cucumismelo, Cantalupensis group), although variable among cultivars, precludes the use of temperatures close to 0 °C for long term storage or transport. Diseases, either associated with chilling or independent from it, are usually the main factor terminating postharvest life of these melons. `Colima', a Western Shipper cultivar highly sensitive to chilling, was used to evaluate chilling and disease response to the following treatments: immersion in water at 60 °C for 1 minute (with or without 150 ppm chlorine), individual packaging (PVC, whole or perforated), exposure to air at 38 °C for 12 hours (with or without individual packaging), and control. After storage for 18 days at 0 °C and a simulated retail period of 3 days at 20 °C, there were significant differences among treatments: chilling was alleviated in heat-treated and especially in plastic-wrapped fruit, and the presence of diseases caused by pathogens such as Alternaria, Cladosporium, Fusarium, and Rhizopus was markedly reduced by heat treatments. Overall, visual quality was high and superior in fruit immersed in water at 60 °C with 150 ppm chlorine due to almost complete supression of diseases. Project financed by FONDECYT 1020882.
Abstract
Three-week old plants of 10 cantaloupe varieties grown in 3-inch peat pots were transplanted to the field from April 15 to 24 for a S-year period. Field seeded plots were direct seeded the same day and 7-10 days earlier.
The yield and fruit weight from transplants were significantly higher than those from field seeded plants. The total soluble solids content of fruit from transplants averaged more than 2 per cent higher than that of field seeded plants started the same date. When field seeded 7-10 days earlier, the difference was not as great; however, total soluble solids were consisently higher in fruit from transplants. Two factors were possibly responsible for the higher yields, fruit weights, and soluble solids. Because field seeded plants matured later, foliar diseases were more severe and plants were also exposed to additional cloudiness and rainfall.
Fruit of transplants matured approximately 14 days earlier than that of field seeded plants started the same date. When field seeding was accomplished 7-10 days before transplanting, fruit from field seeded plants matured only 7-10 days after the transplants.
Although minimal processing increases the perishability of products, largely due to microbial decay, quality changes may be similar between tissues from intact produce and fresh-cut pieces. This study compared pulp quality changes of intact cantaloupe melons and of sanitized fresh-cut pieces (1.8 x 3-cm cylinders) during storage in air at 2.5 (cv. Corona) and 5 °C (cv. Corona and Durango) for 15 days. Quality evaluations included subjective (visual quality, decay, translucency, aroma, off-odor) and objective (color, firmness, SSC) measurements. At 5 °C, visual quality of the pieces was below the limit of salability by day 15 due to decay, whereas pulp from stored melons was excellent. Pulp from intact melons did not suffer from development of translucency as did the fresh-cut pieces. At 5 °C, pulp from intact fruit had higher aroma scores than pieces, but there were no differences in off-odor scores. At 2.5 °C there were no differences in the subjective quality measurements of pulp from intact or fresh-cut pieces. Pulp from intact fruit had higher chroma (at 2.5 and 5 °C) and L* (only at 5 °C) than the pieces after 6 or 15 days, depending on the variety. There were no differences in hue between intact and fresh-cut pulp. Pulp from intact and fresh-cut pieces had similar firmness changes and SSC during storage at 2.5 and 5 °C. We conclude that pulp of intact fruit and fresh-cut pieces had similar quality up to 15 days at 2.5°C; but at 5 °C, the fresh-cut pieces lost intrinsic quality (visual quality, aroma, and color) before the pulp of intact fruit did.